Lap lock sheathing



Oct. 28, 1941. GA. M0\RTHLAND 2,260,720

LAP LOCK, BREATHING Filed July 12, 1940 2 Sheets-Sheet i lNVENTbR Glenn A. Mor'fhland BY I " AT ORNEY.

, wind and capillary attraction,

Patented Oct. 28, 1941 PATENT OFFICE LAP Lock SHEATHING Glenn A. Morthland, Los Angeles, Calif. Application July 12, 1940, Serial No. 345,048

9 Claims.

This invention relates to roofing material and to other types of weather for buildings and other structures, larly relates to such termed roll roofing if used as roof covering, or shingle form, and providesspecial sealing means at the joints or overlaps of such strip and shingle material. g

It is common practice in laying shingles, either of the wood type or of the composition type, and in laying strip roofing, to overlap edges in order to insure adequateweather-proofing. of the ends sought by vent the infiltration of water joints and overlaps oi the shingle.

and. particuin between the No matter how. tight theseshingles and weather strip mate rials are laid, thewater, under the influence oi migrates between the overlaid portions of the roofing material. The .wind enters underneath the coveringbetween the overlap and loosens and sometimes displaces the covering.

In laying shingles, and particularly composi-' material when laid in strips,

proofing coverings.

One such overlap is to pretion type shingles, which are usually coated with granular mineral matter, no sealing. material is laid between the shingles. In laying strip roofing, which like the shingles, is covered with granular'mineral matter, one strip overlaps the adfour inches. It is comthese edges together with joining strip by two to mon practice to cement .an asphaltic material. However, asphalt, when so laid, is not water proof andmoisture does penetrate between the overlapped edges. It is the experience of expert roofers that in laying roofing material, it is extremely difficult such : tact free of capillary passages.

to get a proper bond between the overlapped.

materials and the asphalt due to the rapidcongelation of the hot asphalt in contact with the The cracks and as is well known, is relatively high, and the capillary passages formed by the granular matter, make itimpossible to prevent water from passing between the overlapping portions of the roofing material. In case of the composition shingles, this is aggravated because asphalt is portions of v terioration of the roofing material, and the overlapped edges curl and become displaced soloosening the overlap. It is therefore the practice relatively colder roofing material, and due also to the limited wetting power of the asphalt onv the mineral granular matter.

' natural water absorption of the. asphalt, which,

of passages.

'between the overlapping to make the overlap large, with a consequent waste of roofing material.

These disadvantages are avoided by the present invention, which in its broader aspect pro-.

placed on the obverse side,

therefore throughthe roof. This strip or stopv is preferably made less dense, that is, softer, to permit conformation with the surfaces oftheroofing material, whether it be strip material or shingles, thus forming a firm and solid structure substantially free and preferably entirely free Preferably this raised edge or stop is made integrally with the. strip or shingle, so as to provide no surface of contact with the stripof which it is an integral portion. The surface of the stop is preferably not. mineralized and therefore the surface of the, stop and the bottom of the overlying shingle or strip material is free of mineral matter and the contact of the smoothsurfaces permits of a surface of con- The provision of this stop or block, or dam, acts to dam on or block ofi anyinfiltrating water which gets in is thus prevented from passing roof material, both by thesto'p which acts as a dam, and by the tight overlying portions.

The dams cooperate with the voverlap to hold the overlap to form a locked overlap-structure. The extra width at the dam permits the overlap to be slightly bent at this point, and when it is nailed or otherwise attached'to-the underlying held I course, it is, by the cooperation of the dam, more firmly in place against displacement by the wind and against curling due to weathering.

In laying the strip material of this invention, or the shingle form of sheathing of this invention, the overlap is tacked along the edge of the overlying portion of the strip material several inches away from the dam. The raised portion of the dam cooperates with the strip material and-the tacking to produce a tightjoint. The weight ofthe strip material overlying the dam I and extending some thirty-six inches, irrthe .case of the strip material, presses down upon the dam top to lock the dam in place. The mechanical structure which is thus formed may be likened to a lever. One arm of-the lever is held down by the tacks and the. other arm of portions, and the water I underneath the fitting surfaces or the the lever is held down by the weight of the overlying strip material. The dam actsvas a fulcrum with which this lever action cooperates. The effect of such a construction is to create adownward pressure on the fulcrum due to the cooperating effect of the weighted arms, one weighted by the weight of the overlying strip materiaL'the other held down by the tacking or other cementing means. The positioning of the dam and the overlap of several inches of overlying material also protects the dam against weather, so that it is not exposed to wind, sun and rain. The physicalproperties of the dam, its resilience and structure, is therefore not materially altered and its functioning is not reduced in efficiency.

The provision of this seal will reduce the amount of overlap that must be employed for proper protection, and in this manner will reduce by a material extent the amount of material that is needed to cover any given area, such as a roof.

The dam may be about 1 6 to A; inch thick, more or less. It should not be too thick, as to interfere with the proper laying of the strip or shingle, and should be sufilcientiy thick to give an edge to form a dam. It may be about /2 to 1 inch wide, depending on the nature of the strip material. The dimensions here given are merely illustrative, and may be varied without departing from the nature of this invention.

The strip or dam is preferably formed integrally with the roofing material by rolling the edge of the roofing material less dense than the remaining body of the material. Composition roofing material is formed by rolling asphalt saturated felt between rollers set to a clearance which will give the desired thickness of the finished roofing material. This may be 'done by using either a plurality of rolls, with the edge rolls set with greater clearance than the rolls for the rest of the body of the shingle, or other roll roofing material, or by using a cut out roll so that the clearance between the rolls at the edges will be greater than at the rest of the body of th shingle or roll roofing. The top surface of the edge or dam is preferably free of mineralized matter, and this may be accomplished by depositing the may be provided, one at each edge of the overlying portions. This method would doubly insure the prevention of wind or water passing in between, because there would be a dam at the entrance 'to the overlying portions and any water which might accidentally get through underneath the top overlying portion would be stopped by the dam which would be provided at the back edge of the underlying portion. The space between the dams could be filled with cementing material such as asphalt. I

It is therefore an object of my invention to provide a seal for the surfaces of structures such as wall and roofs, particularly when such surface material is laid as shingles or strips, and particularly when composition type shingles or strips are employed.

It is a further object of my invention to provide a dam or seal between the overlying portions of shingles or strip roof materials.

It is a further object of my invention to provide a seal for. the overlying portions of shingles and strip roofing material of such nature as to create a dam and seal against infiltrating water.

mineral matter only on the remaining portion of the roofing material.

While I suggest the above as one convenient method for making the roofing material, I do not desire to be limited thereto, since many other methods and devices may be employed in manufacturing the form of roll and shingle type of roofing and other covering material included in the invention for which I here make application.

Instead of providing the strip as an integral strip formed on the upper surface at one edge of the stripmaterial, it may be formed at the under surface of the strip material. When the overlap is made the same result is obtained. In either case, the dam may be formed either at the edge or two to three inches, more or less, away from the edge, in which case the strips are overlaid so that the dam or strip or sea] comes between the overlying edges of the roofing material. In employing the dam with strip shingles, the same principle applies, and what has been said about strip roofing also applies to strip shingles. In like manner, individual shingles are handled in a similar manner, as will be evident from the drawings and description thereof.

This invention contemplates alsothe provision of a plurality of such dams. Thus, two dams It is a further object of my invention to provide a dam or seal for overlapping edges of roofing material which is softer than the body of the material and will conform with and form a tight bond with the overlapping edges of the roofing material.

Further objects of this invention will be further understood with reference to the drawings, of which:

Fig. 1 shows a section of composition strip roofing material showing a portion of one width with the dam along one selvedge.

Figs. 1a, lb and 10 show another form of the dam.

Fig. 2 shows the manner of laying of a strip roofing material of Fig, 1 on a roof.

Fig. 3 shows another modification of the composition strip roofing material of this invention showing the positioning of the dams at opposite edges and on opposite sides of the material.

Fig. 4 shows the manner of laying of the strip roofing material of Fig. 3.

Fig. 5 shows the to strip shingles.

Fig. 6 shows another modification of the application of this invention to composition strip shingles.

Fig. 7 shows the application of this invention to individual shingles.

Fig. 8 shows the manner of laying of the shingles of Fig. 7. I

Fig. 9 shows another modification of the application of this invention to individual shingles.

Fig. 10 shows the manner of laying of the shingles of Fig. 9.

Fig. 11 is a section taken along line I l-H of application of this invention Fig. 10.

In Fig. 1, I is the body of the strip roofing which may be of any construction, but in a preferred embodiment of my invention is of the composition type. Such strips are usually made of asphalt saturated paper or other felt material which is rolled to desired thickness by rollers set at a clearance which would give the desired thickness. When they are rolled they become hard and compacted, and during the rolling are coated with a granular, silicious material which is usually. colored. They are usually rolled in large continuous sheets which are 36 inches wide and are wound in rolls.

In the form of my invention shown in Fig. 1,

to wit, the section marked 2, to one thickness,

while rolling the ledge 3 to a greater thickness, which would therefore be less compacted. The mineral matter is laid only on the portion of the strip marked 2, preferably no mineral matter being placed on the surface of the ledge 3.

The laying of this strip material is shown in Fig. 2. Each strip is laid the length of the roof, as is usual for such type, and the adjacent strip or course is overlapped about three or four inches. The overlapping edgelays over the dam 3 and when it is tacked to the underlying portion strip l conforms with and forms a tight bond. The greater resilience, that is, the softer characteristic of ledge 3 as compared with the rest of the body of the strip, permits 3 to conform with the overlying surface of I-a, thus forming a smooth If desired, asphalt may be wiped ,on the underneath portion of l-a, where itoverlies the strip I. This adhesive also helps to permit a tight-fit free of cracks and capillaries.

It will be observed that the courses are nailed or otherwise attached at the overlap and may also be nailed down ahead of the overlap as shown at in Figs. 2, 1a, 1b and 10. The additional thickness due to the dam cooperating with the "tacks,'causes a wedging action which acts to lock the overlap in place and to insure a tight seal at the dam, as shown.

In Fig. 1a. is shown another form of dam structure. In this case the top of the dam is crowned to a curvature approximating the-natural curvature of the roofing as it overlies the dam. This crown provides a closer fit and conformation. In Fig. lb is shown a form of dam wherein the top of the dam is formed as a wedge to conform with the overlying courses, as illustrated in Fig. 1b. These forms. of 1a .and 1b are of greater importance as the height of the dam is increased. If the dam is of suificient height, in the case of a flat top dam, there is a tendency of the overlapping material to contact along the front edge of the dam. If the dam is sufficiently low this point is of tion due to the "give of the dam is suflicient to permit of a tight seal. In Fig. 1c is shown a form of dam which is sloped for a distance somewhat less than the normal overlap which is to be employed, instead of being vertically faced as shown in Figs. 1, 1a and 1b. This slope is provided on the obverse face and the reverse side is preferably flat, as is normal in sheathing such as roll roofing and shingles, as .is here illustrated. The sloping face is preferably unmineralized at 4, in the same manner as shown in Fig. 3. This sloping dam has the advantage of permitting a closer conformation over a larger area than is attained by the dam formation shown in Fig. 1a and Fig. 1b, since it conforms more closely with a larger area of the overlapping portion of the courses. It does not, however, have the advantage present in the dam with the vertical face shown in Figs. 1, la and 1b, and is therefore, in this respect, less efficient. These straight faced dams, as has been explained, act as a definite stop for any. capillary passage of water between the overlapping portions of the courses, breaking upany capillary passages. In the form shown in lc, it is desirable that the wedge extend a few inches towards the lesser importance and the conformaopposite edge, and when laying this form, it is desirable that the overlap be sufficient to overlay the wedge. The overlay is tacked, as shown in Fig. 10. This may be done either through the wedge or beyond the wedge on the overlap, and also, if desired, the overlying courses may be tacked ahead of the wedge to form a look, as explained. The dam forms shown in Fig. 1a, Fig. lband Fig. 10 may be formed in substantially the same way as the flat topped dam, as described above, by the use of rollers cut out to proper shape and properly spaced. Like the dam in Fig. 1, they are preferably unmineralized.

As shown in Fig. 2, any water-which gets under -a and travels between the overlying portions of the strip material, will be stopped by the dam 3. By making the dam integral with the body portion of I, no possible crack or capillary passage is present to permit the water traveling laterally to the roof underneath the strip l-a. The water and wind is held back by the dam andmust, if it is to get underneath the strip I l--a, travel upwardly over the edge of the dam along its top surface before it can go underneath onto the roof. Since the space underneath the overlapped portion of l-'-a may be filled with asphalt, and the passage of water must travel through the capillaries and cracks in the asphalt, and through the capillary spaces between the-grains of mineral matter shown at 2, the positioning of the dam will act as' a definite block preventing any such infiltration underneath l-a onto the roof 4'.

In Fig. 3 I have shown a modification of the strip material in which there is provided on the underneath portion of 1 another dam 5' similar to that shown'at 3, and formed in the same way. The dam forms of Fig. 1a, Fig. 1b and Fig. 10 may be used in place thereof as explained for Fig. 1.

tion of the strip. No mineral matter need be deposited in the portions 4 which usually will underlie the overlapping strips or courses. The strips with dams 3 and 5 are laid in substantially the same way as is shown in Fig. 2, and as illustrated at Fig. 4, but the additional dam tional protection is provided, since the water I must travel underneath the dam 5, then through any open passages in the asphalt filled portion 4,

and is further stopped by the dam 3.

Fig. 5 shows the application of this invention to strip shingles. shingles, and 1 and 1-0. are the dams positioned on the top, i. e. obverse surface, of the respective shingles, similar to tha shown in Fig. 1, Fig. la, Fig. lb or Fig. 10. These dams or ledges may be formed in the same manner as described with regard to Fig. 1, la, lb or 1c; They are positioned near the back edge of the shingle as shown in Fig. 5, the obverse side of the shingle. When they are laid in courses the cut out portion of the shingle overlies the dam as illustrated. The dam'is of considerably less thickness than the width between the notch and the back edge, as

is illustrated. I prefer that the dam be formed integral with the strip and this may be accomplished by rolling a strip of composition mate- The mineral matter may be deposited .only in the portion 2,: which is the exposed por- 6 and 6-11 are the strip rial of twice the width of the strip shingle with a dam rolled into each edge. The continuous strip thus formed may then be cut longitudinally to form two shingle blanks, illustrated in Fig. 5, to form a strip with a dam on one side and from this strip the shingle may be cut.

Fig. 6 shows a modification of the strip shingle shown in Fig. 5, which contains a dam formed on the underneath portion of the strip similarly to that provided in Fig. 3. The second dam, however, is positioned as shown in Fig. 8, on the underneath or reverse portion of the shingle just above the notches, so as to form a double dam in the overlapping portions of the shingles as shown in Fig. 6. This may be accomplished by using a plurality of rolls or using cut out rolls, as will be understood by those skilled in the art. As explained in Fig. 3, and as shown in Fig. 4, a double dammed surface is provided. Thus any water or wind which gets in between the shingles is stopped, first by the first dam 8 and if any gets through that it is stopped by the second dam, T-a.

Fig. 7 shows the application of this invention to an individual rectangular shingle. In this form the shingle is provided with a dam on two sides of the shingle, as shown. The dam may also be of the forms shown in Figs. 1a, lb or 10. The shingle may be made by stamping saturated felt to proper forms as shown. The dams will be less compacted than the exposed portion of the shingle. It is laid as shown in Fig. 8. Shingle 9-0 is laid first. 9-b overlaps 9-c so that one edge overlies a portion of the dam l-c, and all of the dam ll--c. This is continued until a row or course is laid. The next row or course is then laid as shown. Shingle 9 is laid to overlap the overlying portions of 9-c and 9-b and the dams ill-c and Iii-b, and

9a is then laid to overlap the-'portion of the dam l0 and the dam l Land overlaps the shingle 9-42. This is continued for the second course. As will be understood in this art, as many courses as necessary are laid to cover the roof or other surface which is to be protected. This method of laying is of course conventional in using individual shingles of the conventional type, but when used with the form shown in Fig. '7 embody my invention, a continuous dam is established along one course, as illustrated, with dams ill-c and I 0b, and Hi and lll-a respectively. Thus, for example, any water which may pass in between the overlying shingles 9a and 9-b is stopped by the dam H, and any water which may come in between the overlying shingles 9-11 and 9--b, or 9 and 9c, is stopped by the dam iii-b or lllc, and any water which gets between shingles 9 and 9-a or 9-0 and 9-17 is stopped by dams H and ll--c respectively. In this way, a water proof shingle structure is obtained.

As illustrated in- Fig. 9, the shingle may be made with dams of the forms explained in connection with Fig. 7, on all four edges of the shingle, two dams on the adjoining edges of the obverse side shown at is and id, and two dams on the reverse side of the shingle shown at i5 and i1. These shingles, laid in the same manner as illustrated in Fig. 8, form vertical faced dams. Thus, shingle I2e is laid first, l2"'d overlaps l2-e as shown, l2c overlaps l'l-d as shown, and this is continued until one row or course is formed. The shingle l2-b is laid, one edge overlapping l2e, l2a is laid to overlap l2-b and also overlap l2--e and l2d. I2 is then laid to overlap I 2-11 and l2d and l2c. When so laid, a plurality of dams are formed to prevent water from infiltrating underneath the shingles onto the roof. The section taken along ll-ll shows the dam structure which opposes the infiltration of water passing laterally between shingles laid along the row or course. It will be seen that water which tries to get in between the overlapping portions of l2-b and l2--a would have to pass underneath the dams l6-a, l4b, lG-d and l4--e before it can get onto the roof, shown at I1. Any water which passes in a direction perpendicular to the line I l, for instance between shingles l2e and l2a, would have to pass underneath the dam I 5-11 and then over the dam Iii-e, where it contacts the underneath surface of l2a. In this manner the overlying portions of the shingles are,

protected against infiltration of water underneath the shingles or between them onto the roof surface.

If the shape of the shingle shown in Fig. 7 or Fig. 8 is other than rectangular, as for instance if it be a pentagon, hexagon or other form, I form the dam on each of the edges which will be overlapped by the adjacent shingles, as will be understood by those skilled in the art, from the description herein. given.

It will also be recognized that the dam or ledge need not be placed on the edge of the sheathing material, since the results can be obtained by placing the ledge near or at the edge, provided it is sufficiently adjacent the edge to be between the overlying portions of adjacent courses of sheathing. I prefer, however, that it be so positioned that when laid, the edge of the exposed surface of the overlying course or sheathing overlies the edge for several inches, as illustrated and described herein. In this fashion the water must creep between several inches of the overlying surface before it reaches the dam.

It is to be understood that the foregoing de scriptions of embodiments of my invention are not to be taken as limiting of my invention. Various changes and modifications may be made therein without departing from the spirit of the appended claims.

I claim:

1. A sheathing adapted to be laid in anumber of courses, one course overlapping the other, having a dam of softer fibrous composition than the overlying portion of said sheathing positioned adjacent one edge of said sheathing'in such position as to be placed between the overlying edges of the courses.

2. A sheathing adapted to be laid in a number of courses, one course overlapping the other, having a vertically faced dam of fibrous composition softer than said sheathing positioned adjacent one edge of said sheathing to form a total thickness greater than the remaining portion of said sheathing in such position as to be placed between the overlaying edges of the courses.

3. A composition sheathing material composedof rolled asphalt saturated felt, having one portion compacted to a given thickness, silicious mineral matter on said portion, a second portion adjacent the edge of the sheathing rolledto a matter on may be bent over said ity of courses, one course overlapping the other, having a dam positioned on the the sheathing adjacent one edge and a dam positioned on the reverse side adjacent the other edge, the remaining portion of said side being flat.

5. A shingle adapted to be laid in a plurality of courses, having a plurality of edges, a. dam adjacent the edges of said shingles which are overlaid by adjacent shingles when they are laid in said courses.

6. A strip shingle having a dam positioned 'on the obverse side of the shingle adjacent the top edge thereof, said dam being of a width substantially less than the width of the shingle between the notch and the top edge.

I. A rolled roofing comprising a continuous roll of asphalt-impregnated fibrous sheet material compacted and rolled to form a strip',-minera1 said strip for a substantial width of said strip, the remaining width of said strip for a distance of several inches of the other edge of said strip being unmineralized, said unmineralized section being provided with a raised edge portion along the edge of said strip on said unmineralized portion, said raised edge portion comprising fibrous material of greater thickness than said remaining portion of said rolled material, the reverse side of said roll being of substantially uninterrupted flat extent whereby said rolled material maybe laid in overlapping strips, the mineralized section of one strip overlying said raised edge portion and said unmineralized portion of the underlying strip and may be tacked through said overlying portion at a substantial distance away from said raised portion of the underlying strip, whereby said overlying p ion I raised portion to co orm to said underlying strip.

obverse side of ity of overlapped courses, one

8. A sheathing adapted to be laid in a pluralsection of said sheathing extending along and for aconsiderable edge thereof, and being of lesser thickness than another section thereof along the opposite edge thereof, mineral matter on the first mentioned section and said-second mentioned section being substantially free of mineral matter.

9. A roof structure comprising courses of sheet material placed on aroof, one edge of said material having a raised portion, a-second course of sheet material overlying said first course so that one edge of said overlying. course overlaps said raised portion and another portion of said underlying course, said overlap comprising several inches of said overlying material, the non-over lying portion of said second course being in contact with said roof, said courses being tacked so that the overlying portions of said sheet material are held in intimate contact along a surface of contact on the unraised portion of said underlying course and said overlying portion of said roofing being tacked to said roof along a line several inches beyond said thickened portion of:

said underlying course, said tacking points being at a position of said overlying portion where it overlaps and does not contact with said underlying strip, whereby said overlying course is in contact with said underlying course along a surface of contact along one edge and is not'in contact therewith along an adjacent portion of said underlying course and is bent over and in contact with the thickened portion, and then contacts with said roofing in such fashion as to form a weighted lever bond with said underlying portion and conforms with said raised portion.

GLENN A. 1103mm. 

